On July 14, 1965, the American probe Mariner 4 (after the two failed attempts by the Russian Mars 1 and the American Mariner 3) easily reached a distance of 10 000 kilometers from the planet and took 22 pictures of the ground. The details were not very clear, but the general appearance of that portion of the planet, pock-marked with craters, was terribly similar to the desolation on the Moon. For four years those 22 photographs were the only means of debate; a debate that continued to take away any hope of those who hoped to find some form of life. Then, four years later, on July 31 and August 5, two other American probes, Mariner 6 and 7, reached the red planet. They got as close as about 3 500 kilometers from the surface and took respectively 76 and 126 pictures. These images also seemed to confirm the impression created by Mariner 4: there is nothing on the surface of Mars to indicate that it is still an active planet from a geological point of view. And if it is inactive geologically speaking, why should it be active biologically? There were no traces of the canals: immense craters seemed to be the only repetitive structure below a very thin atmosphere (whose surface pressure is equal to only two hundredths of the Earth), consisting mainly of carbon dioxide and only a very small amount of oxygen and water vapor. The surprises started at the beginning of 1972. From that moment on, for an entire year, scholars and Mars enthusiasts were in a continuous state of frenzy. Right on schedule, two other Mars probes were launched on May 8 and 30, 1971 with the purpose of entering an orbit around the planet. The beginning was quite unlucky. The first of the two probes, Mariner 8, failed during its launch and fell back into the Atlantic, not too far from Cape Canaveral. The second probe instead continued its voyage. As it approached the planet, it was obvious that something wasn't right: the disk of Mars, instead of showing clearer and clearer surface features, continued to remain blurry and indistinct. On November 13, Mariner 9 entered orbit at an altitude of a little more than 1 650 kilometers. Its television cameras were capable of showing details down to the size of a football field. But they scanned the surface in vain. Scientists soon understood what was going on: a tremendous dust storm on the surface of Mars obscured the entire planet. Only four strange, dark and rounded stains emerged from the foggy indistinct mass. Mariner 9 continued orbiting under these conditions for about one and a half months. This was a trying period for the Earth-bound technicians and astronomers who had finally hoped to see something. Slowly, the storm abated and the dust settled. And from that moment on (now January 1972), an incredibly varied panorama began to unfold under the eyes of the Nasa experts who, during the 516 days of probe activity, received 7 329 pictures taken from almost all corners of the planet.
On July 14, 1965, the American probe Mariner 4 (after the two failed attempts by the Russian Mars 1 and the American Mariner 3) easily reached a distance of 10 000 kilometers from the planet and took 22 pictures of the ground. The details were not very clear, but the general appearance of that portion of the planet, pock-marked with craters, was terribly similar to the desolation on the Moon. For four years those 22 photographs were the only means of debate; a debate that continued to take away any hope of those who hoped to find some form of life. Then, four years later, on July 31 and August 5, two other American probes, Mariner 6 and 7, reached the red planet. They got as close as about 3 500 kilometers from the surface and took respectively 76 and 126 pictures. These images also seemed to confirm the impression created by Mariner 4: there is nothing on the surface of Mars to indicate that it is still an active planet from a geological point of view. And if it is inactive geologically speaking, why should it be active biologically? There were no traces of the canals: immense craters seemed to be the only repetitive structure below a very thin atmosphere (whose surface pressure is equal to only two hundredths of the Earth), consisting mainly of carbon dioxide and only a very small amount of oxygen and water vapor. The surprises started at the beginning of 1972. From that moment on, for an entire year, scholars and Mars enthusiasts were in a continuous state of frenzy. Right on schedule, two other Mars probes were launched on May 8 and 30, 1971 with the purpose of entering an orbit around the planet. The beginning was quite unlucky. The first of the two probes, Mariner 8, failed during its launch and fell back into the Atlantic, not too far from Cape Canaveral. The second probe instead continued its voyage. As it approached the planet, it was obvious that something wasn't right: the disk of Mars, instead of showing clearer and clearer surface features, continued to remain blurry and indistinct. On November 13, Mariner 9 entered orbit at an altitude of a little more than 1 650 kilometers. Its television cameras were capable of showing details down to the size of a football field. But they scanned the surface in vain. Scientists soon understood what was going on: a tremendous dust storm on the surface of Mars obscured the entire planet. Only four strange, dark and rounded stains emerged from the foggy indistinct mass. Mariner 9 continued orbiting under these conditions for about one and a half months. This was a trying period for the Earth-bound technicians and astronomers who had finally hoped to see something. Slowly, the storm abated and the dust settled. And from that moment on (now January 1972), an incredibly varied panorama began to unfold under the eyes of the Nasa experts who, during the 516 days of probe activity, received 7 329 pictures taken from almost all corners of the planet.
